piecemeal, and if is in this part of the work that help will be most needed. We must begin with a little elementary information.
In inflectional languages most of the words consist of two parts, (1) that which contains the root-idea or ideas, which is called the stem, and may itself be composed of more than one part, and (2) a termination, which has generally no meaning apart from the stem to which it is affixed. The termination may consist of one or more letters or syllables. An important rule is, that in all cases the stem of all the derivatives from any word should contain the true root of that word, which is some times net obvious. To illustrate what is meant, we will take the word chroma, the nominative case of a Greek word meaning "colour." The true root of this word is chromat--, the t having been dropped from the nominative ease, and when the Greeks wished to form a derivative from it, they world always use the true root as a stem; so they obtained chromat-feos, "relating to colour," from which we get chromatic, and we have also achromatism and chromatpgraphy. These are correctly formed, but when Vanquelin, in 1797, discovered a new metal, the compounds of which were remarkable for their varied colours, he called it chromium instead of chromatium, as it should be. More recently the coloured envelope of the sun has been called the chromosphere; it ought to be chromatosphere, and the reader may recollect the outcry which was raised against the word on this account at its first introduction. The generic name, Stromatopora, from stroma, is an instance of correct formation in a similar case. In the two instances just given the misformed words are firmly established, and a change is not only improbable, but perhaps not even desirable. But this is by no means a reason for forming fresh words incorrectly, and there are cases where two modes of spelling exist, when it becomes a question which should be preferred. Thus, there is a botanical genus Portulaca; of this word Portulac: is the stem, and -aceæ is the termination used to denote the whole assemblage of plants of which Portulaca is the type, consequently this Natural Order should be called Portulac-aceæ. In Balfour and the London catalegue this is done, put Bentham and Babington give the title as Portulaceæ, the second ac having been dropped. There is another genus Dipsacus, of which Dipsac- is the stem; its Natural Order should, therefore, be Dipsac-aceæ, and it is so given by Balfour and Babington, but the other two authorities unite in writing it Dipsaceæ. I am aware that there exists « possible explanation of this anomaly, in supposing the termination in these cases to be only -eæ, but it ought certainly to be -aceæ, and the explanation will not apply to the following case. The Natural Order containing Berberis should be named Berberid-aceæ, because the stem of the former word 1a Berborid-, as is seen in the analogous cases of Orchidaceæ from Orchis, Iridaceæ from Iris, and many others. Here Balfour, Babington, and others agree in using the true stem, but the London ctalogue gives Berberaceæ. It is a case of "doctors disagreeing," but a knowledge of the principles underlying those instances will enable the student to "decide" which Doctor it would be better to follow. The tendency is evidently to drop syllables which seem to he superfluous. There is curious instance of this in a branch of science, in which brevity of nomen-
